In switchgear and switchboard systems, run-over buses, such as A-, B-, and C-phase run-over buses can connect between circuit breakers and terminal blocks. For example, in one implementation, run-over bus bars can connect between a load side of a circuit breaker and the terminal blocks that are configured to attach to load cables. Running near these run-over bus bars can be various other bus bars (e.g. horizontal bus bars) that carry A-, B-, and C-phase line current to a line side of the circuit breakers. The horizontal bus bars can be interconnected to three-phase line power, for example. Within such switchgear there may be multiple circuit breakers, each having A-, B-, and C-phase run-over bus bars, an A-, B-, and C-phase horizontal bus bar or other bus bars connected thereto.
In such switchgear, it is desired to move the components as close together as possible to minimize overall space envelope. Such close proximity of various bus bars, such as run-over bus bars and thru (horizontal) bus bars under normal operating conditions is not problematic. However, such close proximity during a short-circuit event can cause substantial forces and possible bending of various bus bar components. If such bending is sufficiently large, it could be possible to have a phase-to-phase short circuit and/or undesirable arcing. Forces encountered during such short-circuit events can be considerable and are approximately inversely proportional to the spacing between the various affected bus bars.
Thus, there is a need to improve various electrical bus bar assemblies to improve their strength and allow such close proximity positioning thereof.